If you're like a lot of folks on here you have a cutting-edge system that spends most of its time idling on a blank screen or running a cool screensaver. It's possibel to donate your spare cycles to cancer and other medical research using Folding@Home.
There are a couple of Ubuntu teams, but we're in the process of attempting to unify behind the team with the most points. Here's the link.
And here's the wiki page.
Also, here's a great post on Hackaday about tips for competitive folding.
Come join the team and have some competitive geeky fun while helping cure diseases! What could be better?